I just run it through comparethemarket.
The longest bit is amassing all the data to the questions (a lot if you have to re-value your house contents).
But once it's done, they have your details on file which makes it a doddle next time - just need to make minor amendments as required. Every time so far we've knocked 100-200 off the quote from an existing insurer.
I also learnt (because it is trivial to diddle the settings and requote) that it makes no difference to price if I declare my car mostly kept on the drive or on the road outside. So I went with the latter as I sometimes do if I have a delivery due.
No real spam from them either - except at renewal time.
Currently Liverpool Victoria do my and SWMBOs car insurance (and they answer their phones, in England, very quickly if you have a query.
Unfortunately LV have some silly conditions regarding window locks on their house insurance (ie you *must* have them, and by default must lock ALL off them - never going to happen in my house). So I went with the slightly more expensive AXA and searched their policy PDFs (electronically) and was pleased to see zero mention of window locks.